2017 S550 4MATIC, W222, 74k miles. last November i replaced the right front strut after it dropped onto the bump stop in a parking garage in Oak Brook. now the left front is doing the early version of the same thing.
once it gets under about 45 overnight, it sits an inch and a half low in the morning. start it, the compressor runs maybe 40 seconds, it comes up level. fine the rest of the day. no stored codes.
the right front was an OEM Mercedes strut, 2,140 for the part at the dealer plus 2.4 hours labor. before i do that again i'd like to know if it's the strut or something upstream. anybody chased this one?
one corner dropping on a 222 with no codes is the strut eight times out of ten. the bladder gets fine cracks at the crimp ring and only leaks when the rubber is cold and stiff. warm day, rubber swells, it seals.
the other suspects are the residual pressure valve on top of the strut and the valve block behind the front bumper on the driver side. you can test the strut in the driveway. lift it on the jack points so the wheel hangs, spray soapy water on the bladder and the fitting up top, lower it back onto the tire and watch for bubbles. the valve block is harder because it's buried.
don't let it go all winter. the compressor is doing extra work every morning and a cooked compressor is the bill that actually hurts. pull the compressor relay while you're at it and look at the pins for heat marks.
this is why i don't miss air springs. steel springs and adaptive dampers on the G90 and the worst it has done is one clunky upper strut mount.
soap test done. slow foam at the crimp ring on the left front bladder, only when it's cold. so the strut.
priced it out. OEM strut is 2,140 again. an Arnott remanufactured unit with a new bladder is 1,020 and comes with a lifetime warranty. a coil conversion kit is 700 but then you drive around with a warning on the dash forever and you've made the car worse.
Arnott on this side, the OEM stays on the right. my indie in Downers Grove says he's done mismatched sides plenty of times with no complaints.
Fargo checking in because the first real cold showed up this week, -4 Tuesday morning. my 2016 S550 sagged at the left rear for the first time ever. hoping it's something small and not a bag. leaving this here so the cold weather reports stay in one thread.
claire, the rears on a 222 are separate air springs, not struts like the fronts, and they're a lot cheaper. 380 or so for a good aftermarket bag. if it comes up level in under a minute every morning it's a slow leak. soap test it the same way before you spend anything.
first real test. -11 in Naperville this morning and the car sat outside at a customer's place overnight. level. both fronts even, compressor ran maybe ten seconds.
the Arnott has 4,300 miles on it. i'll post if it lets go, but for now the 1,100 difference stayed in my pocket. the owner page on mbusa.com still shows no campaign for the suspension on my VIN, so nobody should sit around waiting for a recall on these.
